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April 3, 1956 c. A. PARKER 2,740,532

DIFFERENTIAL ALIGNING AND RETAINING MECHANISM FOR CALCULATING MACHINES Filed April 8, 1950 5 Sheets-Sheet l INVENTOR.

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DIFFERENTIAL. AL'ICNINC AND RETAINING MECHANISM FOR CALCULATING MACHINES Filed April 8, 1950 5 Sheets-Sheet 4 IN V EN TOR. C/mrlPS fl. Par/fer April 3, 1956 c. A. PARKER DIFFERENTIAL ALIGNING AND RETAINING MECHANISM FOR CALCULATING MACHINES 5 Sheets-Sheet 5 Filed April 8, 1950 8 M am 7 z k z w m M MM i W 4 8/ W 2 J a 5 Wm a mp A 5 e 1 r m I C HTI'ORNEY.

United States Patent DIFFERENTIAL ALEGNING AND RETAINING MECHNISM FOR CALCULATING MA- CHlNE Charles A. Parker, Knoxville, Tenn, assig'ror, by mesne assignments, to Burroughs Corporation, a corporation of Michigan Application April 8, 1950, Serial No. 154,817

Claims. (Cl. 235-60) This invention relates to calculating machines of the type which incorporate register operating actuators that are movable through an operating cycle between a fixed limit position of rest and a variable limit position, wherein the variable limits of the actuators are differentially deter mined by stop means which arrest the variable limit travel of the actuators at stop points representing digit positions. The calculators are in operating connection with type carriers which are moved to and from a printing position in accordance with the movement of the register actuators.

An object of the present invention is to provide a novel aligning means for obtaining true alignment of the type carriers when in printing position.

Another object is to provide an aligning means operative to adjust the register actuators into a different position of alignment which provides a point of departure for the the actuators in their return to their fixed position of rest.

Another object is to provide aligning mechanism of such character which is efiective to relieve friction on the cooperating teeth of register pinions and racks which normally occurs when the pinions of a register are shifted into and from mesh with their racks, and which also occurs in the process of total taking when a register pinion is forcibly checked against a zero stop point.

Still another object is to provide retaining mechanism that is automatically effective to retain the actuators in their variable limit positions throughout the remainder of an operating cycle, following removal or disabling of whatever arresting means is utilized to determine and clfect the variable limit stop point for the actuators.

A further object is to provide novel mechanism for eliminating the impact commonly experienced in calculating machines when released actuators travelling under the force of biasing springs are contacted by an oppositely travelling member moving to restore the actuators to their position of rest.

A still further object is to provide mechanism automatically operative in sequence to the normal variable limit determining means to retain the digit stop positions of the actuators as determined by the arresting means.

Other and incidental objects will be apparent to those skilled in the art upon consideration of the following specification in conjunction with the accompanying drawings, in which:

Fig. l is a vertical longitudinal section through the calculating unit and type carrier assembly of a calculating machine in which the invention is incorporated;

Fig. 2 is an enlarged detail, partly in section, of the aligning and auxiliary arresting mechanism of the invention, showing the position of the parts which they normally occupy prior to an operating cycle of the machine;

Fig. 3 is a view similar to 2, but illustrating the position of the parts when the mechanism is operated;

Fig. 4 is a view similar to Fig. 3, and illustrating a step in the process of operation of the aligning and auxiliary arresting mechanism;

Fig. 5 is a horizontal section substantially on the line 5--5 of Fig. 3;

Fig. 6 is a side elevation of the mechanism when the parts occupy the position shown in Fig. 2;

Fig. 7 is a top plan view of the assembly shown in Fig. 6;

Fig. 8 is a side elevation of the mechanism with parts positioned as shown in Fig. 3; and

Fig. 9 is a section taken substantially on the line 9-9 of Fig.

The present invention is herein shown, for purposes of disclosure of an operative embodiment, as incorporated in the calculating machine shown and described in the co-pending application of Charles A. Parker and Clifton K. Rainey, Serial No. 99,081, filed June 14, 1949, now Patent No. 2,696,945. Briefly described, that machine includes a plurality of adding type carriers or bars 20 movable vertically into and from printing position relative to a platen 21. The type bars in printing are struck by a, hammer 22 triggered by cam means on a main drive shaft 24 rotatable in the machine frame by motor means, not shown, under the control of an operator. An operating member OP reciprocates horizontally in the main frame of the machine through one full cycle at each revolution of the drive shaft, there being an operating connection between the shaft and operating member. Each actuation. of the motor means effects one complete rotation of the: drive shaft and correspondingly moves the operating memher 0? through one full cycle between two limit positions in one of which it is at rest. When at rest, the operating member is at its rearmost limit of travel.

Each type bar is moved to and from printing positionv by an individual bell crank lever 27 pivoted at 28 to oscillate in a vertical plane common to the type bar. The long arm of the lever is in operating connection with the lower end of the type bar and, in normal position with the type bar fully lowered out of printing position, the short arm of the lever is held by a latch 29 so that the lever cannot rock to lift the type bar. The latch is biased to engaged position and is releasable by the cainming action of an extension 343 on an actuator slide 31 of the calculating unit C. A slide 31 is paired with each type bar and reciprocates horizontally in the vertical plane common to its associated type bar and bell crank lever. A restore bar 32 extends transversely across the leading edge portions of the slides and normally restrains them against forward movement towards the type bars under the urge of a contractile spring 33. One such spring is connected between the short arm of each bell crank lever 27 and a fixed element 3 5 of the operating member OP.

Each slide 31 has an abutment 35 that is engageable by key set stop pins in a stop pin box assembly S which determine the extent of forward travel of the slides. When the operatin member OP is cycled, those slides permitted movem nt beyond zero position travel forward under the pull of a contractile spring 36; one such spring being con nected between the front end of each slide extension 30 and the operating member element 34. The restore bar will have been moved ahead of the slides under propulsion of the operating element by the time those slides free to move beyond zero position begin their travel past that point. In the course of their forward travel their associated latches 29 are disengaged, whereupon the released bell crank levers 27 rock under the pull of their springs 33 to lift their corresponding type bars into printing position. The terminal portion of the short arm of each released bell crank lever engages behind an abutment 37 on the slide extension 30, so that the printing elevation of the type bar is determined by the point at which further forward travel of the slide is arrested.

At the conclusion of a printing operation the operating member OP moves rearwardly through the second half of its cycle back to its initial position of rest. During this movement the restore bar is retracted and carries back 3 ith t all. ady ased slides The. e racting. s i e aten.- sions rock their associated bell crank levers and pull the type bars down out of printing position. When the slides come to. rest at the; end; of their rearward travel afurther rocking movement is, given the bell crank leversto carry their short arm terminals rearwardly away from the slide extension abutmcnts 37 for reengagement by. the latches 29. This further movement is effected by a pulldown yoke 38 that straddles the long arms-of the entire setv of bell crank levers in an operating connection 39 with the restore bar.

Theregister section is contained within the calculating unitframe. This frame comprises parallel side walls 40 having appropriate transverse connection and mounted on the bottom plate B of themain frame of the machine to extend longitudinally therein in rear of'the platen and the-type barassembly. These walls journal a transverse concentric shaft assembly comprising an inner shaft 42 and an outer sleeve shaft 43 rotatable thereon.

wallsli) support between them atransverse rod 45 which plays in a vertical slot 46 in each wall in accordance with the throw of the cranks on rotation of the inner shaft. in like manner the outer shaft 43 has similar cranks 47 fixedly secure-d thereto interiorly of the walls 49. These cranks, are provided at their outer ends with lateral outwardly directed pins 48 which extend through the walls 40in another pair of the clearance slots 46. The cranks 4.4 and 47 are oppositely directed and are spaced 180 de greesapart.

The rod 45 extends through and pivotally supports the lower ends of a pair of inverted L-shaped links 57 that are vertically slidable on the outer faces of the walls 40. These links support between their upper ends a transverse register pinion shaft 53 which plays inand through a vertical guide slot in each Wall. A set of register pinions 69, one for each numerical order, is freely rotatable on the. shaft 53 between the Walls-4i). In like manner, the pins 48 of the sleeve shaft cranks 47 extend through and pivotally support the upper ends of. a pair of depending L-shaped links 61 that are vertically sli-dable on the outer faces of the walls 49. The depending links support between their lower ends a transverse register shaft 62. which plays inand through a vcrtical'guide slot in each wall. A second and similar set of register pinions 64 is freely rotatable on the shaft 62, each being in vertical coplanar alignment with its corresponding pinion in the upper set. When the register pinions are in. neutral position they are latched against rotationby means of a bar 65 meshed with the pinion teeth under the pull of contractile spring means, not shown. Thelatch bar for each set of pinions extends between the Walls it and projects at each end through a triangular aperture 67 in the wall. Reciprocation of the links correspondingly moves the latch bars, which then arecarnmetl by the sloping sides of the aperlures-67 and shifted laterally against the pull of the spring to disengage the register pinions.

A driving connection, not shown, actuated by the opcrating member OP effects an oscillation of the shaft assembly 4243 to shift the register pinions into operative engagement with racks of the calculating actuator slides justbefore the slides start to move back from'their forward limit positions following a printing operation, whereby the amount of the item is added or subtracted in theregister-in accordance with the setting of the machinev controls for effecting thedirection of oscillation.

The register actuating slides 31 are arranged in parallel relation for horizontal reciprocation in a guide comb it; mounted on, transverse-supports :71 in the calculating unit frame. Each slide is rearwardly bifurcated to provide an upper register stem 72 and a longer lower register stem. 73, inv parallel coplanar vertical alignment. Each stem terminates. in a T-headM disposed, at one sideof arectangul-ar box rack 75 having a top rack bar '76. and

a. bottom;, rack bar 77 toothed to mesh with the adjacent;

Cranks 4.4 fixedly secured on the inner shaft 42 exteriorly of the I egister P nion th t. is dispo e v etween the, tWQ.. e

stem head plays between a pair of longitudinally spaced lugs 73 on the front end portion of both rack bars. These lugs are directed laterally from that side of the rack which faces the rack of the next higher denominational order. A contractile spring 7% connected between a flange of theT-head and the front end of the rack normally biases the rack to the position shown in Fig. 1, with the front lugs '78 abutting the flanges of the T-hcad. The racks are supported and guided by comb plates 86) extending transversely between the frame sides 40 at the front end of the racks, and by comb plates 81 of greater width similarly mounted rearwardly of the plates 80 and spaced therefrom. The comb plates are provided with rearwardly directed vertically convergent fingers dila and Site, respectively, which engage the sides of the racks to maintain them in properly spaced and vertical position. When the racks are fully retracted, their vertical rear ends abut individual rack rests 32;, in which position thespringsv '79 are under tension urging the racks to further rearward.

movement.

Eachregister pinion has twenty teeth representing. two.

series of digits 09. in both the, upper and lower sets each pinion is provided on its side face adjacent the next higher order pinion with a pair of diametrically opposed lugs 91, each of which is a lateral enlargement of a tooth at the zero position. These lugs function in cooperation with interponents i2 in effecting a transfer or carry from each rack to that next in order. Each rackis paired with an interponent located alongside the rack face adjacent the next higher denominational order rack. The interponent body has a horizontally dispose-d shank bifurcated at its frontend to provide parallel arms 93.0011- tiguous to the top and bottom bars of the rack. These arms are supported and guided for horizontal reciprocation in the rear comb 81 in the same manner as the racks. Stoplugs 94 on the arms play in the slots of thecomb and are engageable against a stop plate 81 in front of the slots to determine the forward limit position of the interponent. Each arm has an integral single tooth 95 adapted to coincide with a tooth of the adjacent rack bar and to be engaged by one of the lugs 91 of the register pinion of its paired rack to effect a bodily shift of the interponent rearwardly when the pinion is rotated additively beyond the ninth digit, thereby necessitating a transfer, and to stop the pinion at zero point when the interponentv is in forward stop position and the pinion is reversely rotated.

The mechanism thusfar described in detail forms no specific part of the present invention except as the-details enter into the combination.

Itis known in prior art practice in the field of calculating machines to make use of aligning mechanism which after the differentially limiting means, such asregister pinions on a total takingcycle, for the actuatorshas beenremoved. When the aligning means is thus removed, the actuators are free to moveunder theimpulse of their biasing means until checked by forcible impact against the means which is advancing in an opposite-direction to return the, actuators to. their initial positions.

and strainupon the mechanism. Ina. cycling operation,

when the differential limiting means, such as; keysetstops;

In all such instances; the aligning means must' The force; of the impact is considerable, whichputsan:undue'loadi for the actuators, has not been removed prior to the removal of the aligning means, the actuators are returned to their limiting means. This disrupts proper alignment of the calculator rack teeth, so that when the register pinions are engaged with their racks they must be forced into engagement. In a rapid cycle of machine operation one of the actuators may rebound from its difierential means limit stop and it sometimes happens that the displacement is sufficient to establish a difference of at least one half tooth between the racks. A single blade aligner contacts only this displaced actuator tooth and consequently no alignment action is imparted to the other actuators which are free to vibrate. Under such conditions the following operation of the machine during the cycle may be entirely in error.

It is also characteristic of prior art machines that upon engagement of the aligning means, the actuators and their associated calculator racks are displaced from the digit stop positions at which they were arrested by the agency of the differential limiting means and then returned upon release of the aligning means. The present invention is designed not only to overcome the objectionable displacement characteristics of prior art machines, but also to provide a means for retaining the digit stop positions of the actuators following release or removal of the differential limiting means and throughout the remainder of the operating cycle.

The specific embodiment of the mechanism for accom plishing the foregoing objects, as disclosed in the drawings, comprises a ratchet bar 9:: in association with each actuator 31. Each ratchet bar is pivoted at its forward end on a common pivot shaft 97 that is journalled transversely of the bank of actuators between the ears 98 of a swinging yoke 99 that is, in turn, pivoted for horizontal oscillation on a shaft 193. The shaft 100 parallels the shaft 97 in forwardly spaced relation therefrom and is journalled at its ends in mounting blocks 101 that are rigidly secured to the adjacent inner faces of the walls 40 of the calculating unit frame. All the ratchet bars 96 are disposed in identical transverse alignment and in parallel spaced relation that is maintained by the depending fingers 192 of a comb plate 103 that is secured by attaching elements 104 transversely across the calculating unit on the upper face of a transversely extending retainer plate 195 that is itself secured by attaching elements iii? to the mounting blocks 101. The rear end portion of each ratchet bar 96 lies flatly against the adjacent side face portion of its associated actuator slide 31, so that the actuators are free to move relative to their ratchet bars at all times except when the bars are presented in stop relation by means hereinafter described.

The retainer plate 105 is a flat horizonal plate that extends transversely of the calculating unit just above the upper fiat edge 106 of each ratchet bar. The plate is so disposed relative to the shaft 97 that the shaft underlies the midportion of the plate. By virtue of this arrangement, when the ratchet bars are in normal inoperative position the forward end portion of each ratchet bar flatly contacts the under face of the plate 105 so that the bars are prevented against oscillation in a vertical plane on their mounting shaft 97. Directly beneath the shaft 97, each ratchet bar is provided with an ear 108 depending from the bottom edge of the bar and which forms a point of attachment for a contractile spring 109 which is secured at its other end to a transverse anchor rod 110 that is supported at its ends in the mounting blocks 1 .91 in. parallel spaced relation to and beneath the yoke shaft 100.

The assembly of ratchet bars 96 is disposed above the upper comb plate 70 in which the register actuators are guided. Each actuator has rigidly secured thereto a toothed pawl 111 that is fixed to the side face portion of the actuator in the vertical plane of the particular ratchet bar with which the actuator is associated. For cooperation with the tooth 112 of the pawl, each ratchet bar is provided along its under edge with a series of ratchet teeth 113 that represent digit stop positions in numerical order. The pitch of the teeth 113 is such that when they are presented to the actuator pawl they will stop the actuator against forward movement, in the direction in which the actuators move when travelling from their fixed limit positions of rest. The teeth, however, merely ride upon the pawl when the actuators are moved rearwardly, in the direction away from their variable limit positions and toward their fixed position of rest. In the normal position of the parts, as shown in Fig. 2, the ratchet bars 96 are held against movement under the urge of their springs 109 by their contact with the retainer plate 105, as described.

At this point attention is called to the cycle of operation of the machine. When the machine is at rest the parts occupy the position shown in Fig. 2. As the operating member OP, see Fig. 1, starts forward in its first half cycle, it picks up and carries forward the restore bar 32 so that the restraint imposed on the actuators by the bar is removed. Forward travel of the operating member increases the tension on the springs 36 whereupon the actuators 31 are moved forwardly from their rear limit position of rest and they continue forwardly until they are differentially arrested by any instrumentality which is brought into play to create their variable limit stop positions. During this period the ratchet bars 96 remain in elevated position free of engagement with the actuatorcarried pawls. When the restore bar 32 approaches its forward limit of travel it engages mechanism, later .described, which actnates the ratchet bars through an initial movement, into the position of parts shown in Fig. 4, which presents the teeth 113 in stop relation to the pawls 111 of the various actuators. in this initial movement and stop presentation, the teeth 113 have their vertical stop faces disposed slightly forwardly of and out of abuting contact with the forward vertical edge of each actuator pawl tooth 112. At this point all the actuators are held in their differential stop positions by the usual differential arresting means previously described. However, if for any reason the differential stop means should be removed, the actuators will tend to move forwardly under the urge of their springs 36 but will immediately be arrested by the stop engagement of the pawls 111 with the teeth of the ratchet bars, so that their digit stop positions as determined by the differential arresting means will be retained. In the last portion of its forward travel, the restore bar 32 further actuates the mechanism, later described, to impart a descending toggle action to the ratchet bars and their yoke 99, whereby the ratchet bars are given a slight rearward movement which brings their teeth into full engagement with the actuator-carried pawls, so that the actuators are backed up slightly in a retrograde move ment without actually displacing them from their digit stop positions. This retrograde movement of. the actuators, although very slight, is sufficient to relieve the tension on the calculator racks and their associated pinions when the pinions are forcibly checked at their zero points in a total taking. operation. By thus relieving the tension, the pinions are enabled to be withdrawn from mesh with their racks easily and speedily at the conclusion of total taking.

When the restore bar arrives at its forward limit of travel it actuates mechanism described in the following paragraph which latches the ratchet bars in their depressed operative position. This latched relation of parts is maintained until the restore bar 32 nears the end of its return movement during the second half of the operating cycle, at which time the latch is released so that the ratchet bars may be automatically restored to their normal elevated and inoperative position. In moving rearwardly the restore bar successively engages the forward end portions of the differentially positioned actuator slides 31 and carries the slides back to their normal limit positions of rest. During rearward travel of the restore bar until greases the bar contacts and moves the actuator and racks, the relative differential stop positions of the racks are maintained by the cooperative action of the pawl and ratchet mechanism. This mechanism permits free rearward movement of the actuators but prevents any forward movement.

it is here pointed out that the retrograde movement of the actuators under the descending toggle action of the ratchet bars 96 brings all of the actuators and their corresponding calculating racks into definite position of true alignment of the rack teeth transversely across the entire calculating unit. This position of definite alignment is Spaced slightly rearwardly of the point at which the actuators are initially stopped by the differential arresting means, and this position of definite alignment therefore becomes the point of departure for the actuators when they begin their travel rearwardly back to their initial positions of rest. At the same time, the retrograde aligning movement imparted by the descendin ratchet bars is transmitted to the type carriers so that they are simultaneously brought into true alignment at their printing position. This align ing movement has a further and advantageous effect in that it serves to dampen vibrations incident to the initial movement and stoppage of the type carriers and actuators in their differential stop positions.

The mechanism for bringing the ratchet bars into operation in the performance of their aligning function and their function of an auxiliary actuator arresting means is best shown in Figs. 69. It comprises an actuator lever 114 that is arranged for oscillation in a vertical plane in parallel spaced relation to the outer face of the right hand side wall 40 of the calculating unit frame. At its upper end, which extends above the top of the adjacent portion of the wall 40, the lever has attached thereto a saddle bracket 115 which overlies the upper edge of the wall ll) and which has rigidly secured thereto a depending lug 116 interiorly of the Wall and which is secured at its lower end to the right hand end portion hit of the swinging yoke 99, so that the yoke shaft 1% provides the fulcrum point for the actuator lever. in the normal position of the parts, indicated in Fig. 6, the shank of the lever 114 is inclined downwardly and rearwardly with its lower end normally retained against a stop 117 carried by a guide 118 secured to the adjacent side wall of the calculating unit frame. The actuator lever is biased to this position of engagement against the stop 117 through the pull of a contractile spring 119 that is anchored at its front end to the lower end portion of the actuator lever and which is anchored at its rear end to the upper short arm 120 of a bell crank lever that is pivoted as at 121 to the adjacent side wall 40 for oscillation in a vertical plane. The bell crank has its long arm 122 inclined forwardly and upwardly to ride over a lateral stud 123 carried by the actuator lever 114. The forward end of the long arm 122 is provided with a recess defining a shoulder 124 that is adapted to drop behind the actuator stud 123 to maintain the parts latched engagement in the position shown in Fig. 8.

The restore bar 32 has mounted thereon a contact bracket 125 that has a rearwardly extended portion 126 disposed for camming engagement with the forward edge of the short arm 12b of the bell crank lever, as shown in Fig. 6. The contact bracket also is provided at the front of the restore bar with a bowed terminal 127 that is disposed in the plane of the actuator lever 114 for contac thcreagainst during forward travel of the restore bar. The biasing force of the spring 119 normally retains the actuator lever 114 in its normal unlatched position, as shown in Fig. 6, in which it is effective to maintain the mounting shaft 97 of the ratchet bars in elevated position with the forward ends of the ratchet bars contactetl and held by the retainer plate 105, and against the urge of the springs 109. In the course of its forward travel, when the restore bar 32 reaches the actuator lever 114, its contact elemcntlZl' engages the actuator lever to rock it forwardly to an initial movement which, as best shown in Fig. 4, is enough to lower the shaft 97 sumciently to permit the bias of the springs 109 to become effective and to draw down the rear end of the ratchet bars 96 whereby their teeth 113 are presented for stop engagement by the pawl teeth 112 on the actuators Bil. As previously explained, this initial depression of the ratchet bars occurs while the differential arresting means is still effective to hold the actuators at their variable li of travel as determined by the arresting means. As the Nature bar continues forwardly the actuator lever 11 i is further rocked into a position which carries its stud 123 forwardly of the shoulder 124 on the long arm of the bell crank lever, so that under the urge of the spring 119 the long arm of the bell crank lever drops down into the position shown in Fig. 8, whereby the actuator lever R14 is latched against return movement. This further movement of the actuator lever ill i into latched position further carries down the shaft W and imparts a toggle action to the assembly comprising the swinging yoke 99 and the ratchet bars. This toggle action forces the ratchet bars downwardly and rearwardly to accomplish the retrograde movement of the actuators as previously described. When the restore bar moves resrwardly during the second half of the operating cycle, the actuator lever 11 i remains in latched position until the contact cam bracket portion 126 on the bar engages the short arm 12-3 of the bell crank lever 122 and cams it rearwardly to lift the shoulder 124: out of latched engagement with the stud 3123. This action takes place when the restore bar is moving into its position of rest at the conclusion of an operating cycle. As soon as the actuator lever ill is released from its latched engagement, the bias of the spring 119 becomes effective to rock the lever rearwardly against its stop .llli and thereby to efiect a corresponding elevation of the shaft 97 to bring the forward ends of the ratchet bars as again into contact with the retainer plate 1%. in this movement the ratchet bars are released from the actuator pawls and are re stored to their initial inoperative positions. A holddown element 128is pivoted to swing vertically from a shaft 129' extending transversely between the side walls of the calculating unit frame. The hold-down extends transversely across the rear ends of all the ratchet bars and prevents upward overthrow of the ratchet bars in returning to their elevated position. When the actuator slides 31 move forward their leading edges engage the swinging hold-down element and carry it forwardly out of obstructing position.

Although the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention as claimed.

-l claim:

1. In a cyclically operable calculating machine having a differential actuator, means to urge said actuator from a normal position through a series of advanced positions, a restoring member normally retaining said actuator in said normal position and reciprocating in each machine cycle first in an advancing stroke permitting movement of said actuator from said normal position through said advanced positions and subsequently in a restoring stroke returning said actuator to said normal position, and means engageable with said actuator to arrest advance thereof at any of said advanced positions and subsequently disengageable from said actuator prior to return movement thereof by said restoring means; an aligning and retaining means including a movable support, pawl and ratchet elements, one of which elements is on said actuator and the other of which elements is mounted on said movable support, means normally maintaining said movable support in a position disengaging said pawl and ratchet elements, means operated by said restoring member toward the end of its advancing stroke to move said support to engage said pawl and ratchet elements and actuate them to retract said actuator slightly from its position of arrest by said arresting means, and means automatically retaining said support in such moved position after movement thereto but released by said restoring member near the end of the return stroke thereof.

2. In a cyclically operable calculating machine having a difierential actuator, means to urge said actuator from a normal position through a series of advanced positions, a restoring member normally retaining said actuator in said normal position and reciprocating in each machine cycle first in an advancing stroke permitting movement of said actuator from said normal position through said advanced positions and subsequently in a restoring stroke returning said actuator to said normal position, and means engageable with said actuator to arrest advance thereof at any of said advanced positions and subsequently disengageable from said actuator prior to return movement thereof by said restoring means; an aligning and retaining means including a crank, pawl and ratchet elements, one of which elements is on said actuator and the other of which elements is pivoted on said crank, an arm connected to said crank and extending into the path of said restoring member for operation thereby near the end of its advancing stroke to rock said crank to engage said pawl and ratchet elements and actuate them to retract said actuator slightly from its position of arrest by said arresting means, a latch element on said arm, a latch lever engageable therewith to retain said arm and crank in said rocked position, and means urging said arm and crank to disengage said pawl and ratchet elements and urging said latch lever to latching position, said latch lever being movable to releasing position by said restoring member near the end of the return stroke thereof.

3. In a calculating machine including type carriers movable to and from a printing position and register actuators operatively connected to said type carriers and movable from and to rest position during a cycle of operations in response to control by a cycling member, arresting means adjustable into and out of position for engagement with the actuators for stopping said actuators in selected positions during movement from position of rest, aligning means operative in sequence with said arresting means to engage said actuators in arrested position before 10 disengagement by said arresting means and positively to return said actuators a short distance toward rest position into aligned position and for holding same in aligned position until positively engaged by said cycling member for return to position of rest and operatively engaging said actuators until returned to position of rest and means operative in response to return of said actuators to position of rest for restoring said aligning means to their original position of adjustment.

4. In a calculating machine as claimed in claim 3, in which the aligning means comprises a pawl fixed to the actuator and an arm having ratchet teeth on one edge thereof and pivotally mounted at one end on a lever rockable to adjust said toothed arm to engage said pawl to retract said actuator slightly from said position of arrest, and in which the means for operating said lever comprises a swingable arm operatively connected to said lever, means responsive to movement of said cycling member during the latter portion of the first half of the cycle of operations for shifting said arm into operative position, and means for holding said arm in operative position until return of the cycling member to its original position of adjustment.

5. In a calculating machine as claimed in claim 4 in which the means for holding said arm in operative position comprises a bell crank lever pivoted intermediate its ends and having an abutment in one end portion operatively engaging a stop on said arm to hold the arm in operative position, and means responsive to return of the cycling member for disengaging the stop from the abutment whereby the arm returns to its original position of adjustment.

References Cited in the file of this patent UNITED STATES PATENTS 1,318,397 Malcher Oct. 14, 1919 1,591,664 Ekman July 6, 1926 1,813,037 Ens July 7, 1931 1,817,451 Gubelmann Aug. 4, 1931 2,003,783 Fuller June 4, 1935 2,152,320 Llorens Mar. 28, 1939 2,501,444 Gollwitzer Mar. 21, 1950 2,558,631 Suter June 26, 1951 FOREIGN PATENTS 4,376 Great Britain June 19, 1912 

